The U.S. had more hate groups last year than at any point in at least the past two decades, according to an organization that tracks white supremacists and other far-right extremists.

The Southern Poverty Law Center said Wednesday that the 1,020 groups it counted in 2018 is the most since 2011 and the highest number since the center broadened its survey of such groups in the 1990s. Last year’s tally also represents a 7 percent increase over the 954 groups that the Alabama-based law center counted in 2017.

Heidi Beirich, director of the law center’s Intelligence Project, said the count reflects an “enlivened American hate movement” that has been growing for the past four years.

“This time period dovetails with (Donald) Trump’s campaign and then his presidency, a period that has seen a 30 percent increase in the number of these groups,” she said. “In the three years prior to that, during the waning years of (Barack Obama’s) presidency, hate groups were actually on the decline.”

Some organizations on the list have criticized or even sued over the hate-group labels, accusing the law center of political bias.

The law center, based in Montgomery, Alabama, defines a hate group as an organization that attacks or maligns an entire class of people. Beirich said the law center stands by its designations and denied its list unfairly targets conservative groups.

“I’ve never thought of it as a conservative position to defend, for example, defaming gay men as being child molesters or pedophiles. The kind of speech that we call out is of that nature. It’s defamatory. It’s negative propaganda,” she said.

Liberty Counsel Inc., a Florida-based legal advocacy organization, sued after a website that maintains a charity database flagged it and 45 other nonprofits for being labeled as hate groups by the law center. A federal judge in Virginia threw out that lawsuit. A federal magistrate in Alabama recommended the dismissal of a separate lawsuit that accused the law center of defaming a Florida-based evangelical ministry by designating it as a hate group.

The number of white nationalist groups counted by the law center increased from 100 chapters in 2017 to 148 in 2018. But the number of Ku Klux Klan chapters dropped for the third year in a row, falling to 51 chapters in 2018 from 130 in 2016, according to the law center’s report.

“The KKK has not been able to appeal to younger racists, with its antiquated traditions, odd dress and lack of digital savvy. Younger extremists prefer Fred Perry polo shirts and khakis to Klan robes,” the report adds.